In most cases pro players don't want to do autographs or conversate with fans. They just want the money and to be left alone. They won't do the leg work to give pool the reputation it needs and build a fan base by treating those fans with the respect to make them want to attend more events, spend more time on the table at their local room, and buy more pool products to make the sport thrive.
I have to disagree. There are a few that aren't very sociable with the fans but they're the minority, not the majority. I've found the majority to be very approachable and more than willing to smile for a picture or sign an autograph. Many can be found sitting in their sponsors booth during Valley Forge, BCAPL, & the BCA expo.
On the other hand, other pros in other pro sports are not even remotely as accessible as pro pool players and when you do get a chance to get up close, it seems the majority are the ones that don't want to be bothered, and the personable guys willing to smile for pictures and sign autographs are in the minority.